1st Quarter, 2011 Vol. 17 No. 1

SEA SURFACE TEMPERATURE (SST)

A moderate-to-strong La Niña continued during December 2010 as reflected by well below-average sea surface temperatures (SSTs) across the equatorial Pacific Ocean. All of the Niño indices were –1.5°C at the end of December, except for the easternmost Niño-1+2 region. The subsurface oceanic heat content (average temperatures in the upper 300m of the ocean) continued to reflect a large reservoir of below-average temperatures at depth in the central and eastern equatorial Pacific. Convection remained enhanced over Indonesia and suppressed over the western and central equatorial Pacific. Also, enhanced low-level easterly trade winds and anomalous upper-level westerly winds continued over the equatorial Pacific. Collectively, these oceanic and atmospheric anomalies reflect the ongoing La Niña.